How Does a Photon Experience Space and Time?

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Discussion Overview

The discussion revolves around the nature of photons and their relationship with space and time. Participants explore concepts related to the experience of time by photons, the implications of photons moving at the speed of light, and the paradoxes that arise from these ideas. The conversation touches on theoretical implications, conceptual challenges, and interpretations of electromagnetic wave behavior.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question the idea that photons experience no time, suggesting that if they are created and destroyed, they must experience time in some form.
  • Others argue that there is no inertial reference frame in which a photon is at rest, making the concept of a photon's experience of time self-contradictory.
  • A participant proposes that the relationship between electric and magnetic fields in a photon's frame is problematic, as change requires time.
  • Some contributions suggest that the notion of a universe without time is speculative and unrealistic.
  • One participant asserts that particles and light do not experience time, emphasizing that memory and time tracking are human attributes.
  • There are challenges to the understanding of reference frames, with some participants indicating that a reference frame cannot be defined for a photon, as it requires massive particles.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the nature of photons and their experience of time. There is no consensus on the implications of photons moving at the speed of light or the validity of various interpretations of their behavior.

Contextual Notes

Discussions include unresolved assumptions about the definitions of time and space in relation to photons, as well as the implications of electromagnetic wave behavior. The complexity of defining reference frames in the context of special relativity is also noted.

QuantumHop
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Where does the photon "live"

What happens to space-time when you remove the time?

Its said that the photon experiences no time, it seems to be generally accepted that a photon is emitted by one atom and then instantly absorbed by another in its reference frame but this seems paradoxical. If it was emitted by an atom and then never experienced time it would exist forever. The very fact it is created and then destroyed suggests it must experience time. Is it that the distance between the atom that emits it and the atom that absorbs it is zero or does it occupy all of "space?" until its absorbed?

How is it waving in our reference frame?

We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame there is no time and without time an electric field cannot create a magnetic field! change requires time. Does this mean its both waves at once until we observe it?

When photons are created they radiate outwards as a wave but it can only be detected at one point in space, this is also crazy because it would suggest that if you were in a room with a light bulb and you put a photon detector at any point in the room it should absorbed all the photons leaving the rest of the room dark.

If the laws of nature have courts then the photon should stand trial for giving me headaches.
 
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QuantumHop said:
We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame [...]

There is no such frame. There is no inertial reference frame in which a photon or electromagnetic wave is at rest. It's a self-contradictory concept.

https://www.physicsforums.com/showthread.php?t=511170
 
Last edited:


jtbell said:
There is no such frame. There is no inertial reference frame in which a photon or electromagnetic wave is at rest. It's a self-contratictory concept.

https://www.physicsforums.com/showthread.php?t=511170

Thanks for the link, I'm sure the answer to my question is in there but I still don't get it.
If its still moving at speed c in its reference frame then how come its not experiencing time? how can it be in motion and yet not experience time when motion requires time.
 


QuantumHop said:
We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame there is no time and without time an electric field cannot create a magnetic field!
I don't think there's anything to support this view. The two fields are in phase but perpendicular. You might just as easily say that the magnetic component creates the electric field.

See the Wiki article http://en.wikipedia.org/wiki/Electromagnetic_radiation
 


QuantumHop said:
What happens to space-time when you remove the time?

Its said that the photon experiences no time, it seems to be generally accepted that a photon is emitted by one atom and then instantly absorbed by another in its reference frame but this seems paradoxical. If it was emitted by an atom and then never experienced time it would exist forever. The very fact it is created and then destroyed suggests it must experience time. Is it that the distance between the atom that emits it and the atom that absorbs it is zero or does it occupy all of "space?" until its absorbed?

How is it waving in our reference frame?

We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame there is no time and without time an electric field cannot create a magnetic field! change requires time. Does this mean its both waves at once until we observe it?

When photons are created they radiate outwards as a wave but it can only be detected at one point in space, this is also crazy because it would suggest that if you were in a room with a light bulb and you put a photon detector at any point in the room it should absorbed all the photons leaving the rest of the room dark.

If the laws of nature have courts then the photon should stand trial for giving me headaches.

I hear ya,

perhaps the photon asks the same for something that doesn't have to move at c. It's equally odd isn't? The photon wonders how we include time in our observations of it.

The last paragraph is ignoring quanta of EM isn't?
 


QuantumHop said:
What happens to space-time when you remove the time?[..]
A universe without time is mere speculation. - it isn't realistic at all.
 


QuantumHop said:
jtbell said:
There is no such frame. There is no inertial reference frame in which a photon or electromagnetic wave is at rest. It's a self-contradictory concept.

https://www.physicsforums.com/showthread.php?t=511170
Thanks for the link, I'm sure the answer to my question is in there but I still don't get it.
If its still moving at speed c in its reference frame then how come its not experiencing time? how can it be in motion and yet not experience time when motion requires time.
Why, after jtbell told you, there is no reference frame for a photon, do you quote him and then ignore him by repeating the same self-contradictory question?

Before you can ask meaningful questions about a reference frame, you need to learn and understand what it is and how it is defined. Part of that definition requires clocks at rest at different locations in that reference frame. You cannot build a clock out of just photons, you need massive particles which cannot travel at c. Therefore, the definition of a reference frame is meaningless for a photon.

The definition of a reference frame also requires the use of a rigid ruler which also requires massive particles. You cannot build a ruler out of just photons. Therefore, your first question, "What happens to space-time when you remove the time?", when applied to a photon should more appropriately be "What happens to space-time when you remove the space and the time?" Do you see how meaningless it gets?

It's not that "the photon experiences no time", it's that the photon has no experience. You need to learn what a reference frame is and how it is used in Special Relativity before this will make sense to you.
 


QuantumHop said:
If its still moving at speed c in its reference frame then how come its not experiencing time?
It is NOT moving at c in "its reference frame", there is simply no such frame which can be called "its reference frame".
 


QuantumHop said:
What happens to space-time when you remove the time?

Its said that the photon experiences no time, it seems to be generally accepted that a photon is emitted by one atom and then instantly absorbed by another in its reference frame but this seems paradoxical. If it was emitted by an atom and then never experienced time it would exist forever. The very fact it is created and then destroyed suggests it must experience time. Is it that the distance between the atom that emits it and the atom that absorbs it is zero or does it occupy all of "space?" until its absorbed?

Particles and light don't experience time. When an electron absorbs a photon, it's always the first time, i.e. it has no memory. People have memories, they track time.
 

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